Dual water heating systems



Nov. `26, 195,74- M. A. 'rl-ioMAs 2,814,279

\ DUAL WATEWHEATING sys'rms original Filed .Jury 11, 1944 2 sheets-siegt1 HIS AGENT.

Nav. 26, 1957 original Filed .myni '1944 M. A. THOMAS DUAL WATER'HEATING sYsmas 2 Sheets-Sheet 2 N cu Marh'n A Thomcrs Q Y INVENTOIL .BYn

so l' a Hrs AGENT.

DUAL WATER HEATING SYSTEMS Martin A. Thomas, Wichita Falls, Tex.,assignor of onethird to Wayland D. Keith, Wichita Falls, Tex.

@riginal application .luly 11, 1944, Serial No. 544,431,

now Patent No. 2,604,265, dated July 22, 1952. Divided and thisapplication December 12, 1951, Serial No. 261,198

4 Claims. (Cl. 122-18) This invention relates to improvements in dualwater heating systems, and more particularly to water heating systemsutilizing thermal control for the heating media, as for instance,turning on the gas, or other source of heat, when the water has cooledto a predetermined temperature.

This application is a division of application Serial No. 544,431, ledJuly 1l, 1944, by Martin A. Thomas, for Water Heater Systems, and is nowPatent No. 2,604,265, issued July 22, 1952.

The storage type water heater is the most widely used at the presenttime, but this type system can be materially improved as to eiiciency,and lower cost ofv operation, yet maintaining all the advantages of thesystem, as well as of an instantaneous system.

Various thermal controlled water heating systems have been proposedheretofore, but for the most part, these have been inadequate, as thelag between the time when the water is turned on and the time at whichthe fuel ignites at the burner is so long that au accumulated amount ofcold water has time to ilow into the system, before the burner startsoperating.

An object of this invention is to provide a water heating system whichwill maintain two different water temperatures for withdrawal and whichare controlled by a single thermostat.

Another object of the invention is to provide a coil within a ue of thewater heating system to further heat the water to make it possible fordierent temperatures to be withdrawn from a single water heater tank.

Still another object of this invention is to provide a thermo-controlvalve to direct cold water into close proximity to the thermostat foraccelerated actuation of the igniting of the fuel at the burner.

Yet another object of the invention is to provide a water heating systemwhereby the thermostatic control turns on the gas or other heating mediaalmost simultaneously upon the withdrawal of hot water from the system.

The above and other objects and features of the invention will beapparent to those skilled in the art, from a consideration of thefollowing detailed description taken in conjunction with theaccompanying drawings, in which:

Fig. 1 is a vertical sectional view through a form of the invention,with parts broken away and shown in section, t show the details ofconstruction; and

Fig. 2 is an enlarged longitudinal sectional view of a thermal valveswitching mechanism applied to a burner, with parts in elevation.

With more detailed reference to the drawing, the numeral 51 designates atank for heating water, which has a primary burner 2 and a secondaryburner 2 in the combustion chamber 53 at the lower portion thereof. Avent or tlue is provided through the top of the tank 51 to pass oi theproducts of combustion from the chamber 53.

A diverter valve, designated generally at 57, as shown in Fig. 2, isprovided for controlling the supply of water from pipe 58 to the watertank 51. The diverter valve 57 has an inlet opening 13 therein anddischarge openings 14 nited States Patent C) F ICC and 15 therein. Thewater inlet pipe S8 is connected with inlet opening 13 and the opening14 is connected to a water outlet pipe 59, which pipe 59 leads to aperforated tube 60 within the upper portion of storage tank 51, with theperforations designated at 60a being within tube 60 at spaced intervalstherealong on a side thereof. A pipe 55 is connected to diverter valve57 and is in communication with discharge opening 15 in diverter valve57.

The valve 57 has a disc 16 secured to an axial plunger shaft 17. A disc18 is adjustably secured on a threaded portion 19 of the plunger shaft17. A nut 20 is used to secure disc 18 in adjusted position. These discs16 and 18 are positioned within a chamber 21 of the valve 57, so as 'toseat alternately on valve seats 22 and 23, respectively. A sleeveportion 24 of the casing of the valve 57 carries the seat 23, and isremovably attached to the valve body S7 so the seats and discs of thevalve may be properly assembled or reconditioned. A spider 26 is formedwithin the sleeve portion 24 so as to guide the axial plunger shaft 17.

A .brace 28 is secured in bridging relation to the opposite end of thecasing of the valve 57 for attachment of a threaded tubular member 29.The tubular member 29 is screw-threaded through a plate 31, which plate30 is attached to the wall of the tank 51, over an opening therein atone side of the chamber 53. A lock nut 31 secures the tubular member 29in a xed position relative to the plate. On the end of the tubularmember 29, inside the chamber 53, is secured a bi-metallic member 32which is adjustably secured in place by nuts 33. Another section of thebi-metallic member 32 is adjustably secured thereto by a clamp 35. Theouter extremity of bi-metallic member 34 is secured to the axial plungershaft 17 by nuts 36. The inner end of the tubular member 29 is held inspaced relation to burner 2 by a brace 37 which is adjustably mounted onthe tubular member 29 by nuts 38.

A heating coil 63 is disposed in the upper portion of the combustionchamber 53 and extends through the llue 54 in which it is suspended by abrace 64. The coil 63 is connected `at one end with a pipe 65 whichextends in the tank Sl to an upper portion thereof but it isdiametrically disposed rom perforated tube 60. The coil 63 has a normaloutlet into a pipe 66 connected therewith and with an outlet pipe 56 tosupply hot water to the desired point. However, a by-pass 67interconnects the pipe 66 with a pipe 68 through a check valve 69, thepipe 68 opening into the top of the tank 51 so water may lbe circulatedthrough coil 63 and back into tank 51. A valve 70 is provided betweenthe pipes 68 and 5'6, which valve, connecting these together, isnormally closed to prevent water from owing from the pipe 68 into thepipe 56, unless it is desired that the water flow between these pipes.

A drain valve 71 may be located in the lower portion of the tank 51 ifdesired.

A fuel supply line 72 has a thermostatic valve 73 and a thermo-element73a therein, for supplying gas or other fuel to the burners 2 and 2. Apilot light burner 74 is provided for igniting the burner 2.

Operation In the operation of the system, as shown in Fig. l, cold waterenters the system through the supply pipe 58. With the diverter valve 57in its normal position, as shown in Fig. 2, the valve 18 being open, asmall supply of water is directed immediately through the pipe 59 to theperforated tube 60, Fig. 1, from which it is directed outwardly throughperforations 60a against the thermostat element 73a of the valve 7 3,forming a small localized cool water zone surrounding and cooling saidthermostat. With the cool water zone located within the normally hotWater zone, this cool water will gradually become heated to operate thethermostatically controiled fuel supply valve 73 toward its closingposition, but only after suicient time has elapsed to permit the heatingof the cool water as it comes into the tank 51. The thermostat 73 is ofthe conventional type that opens a fuel valve when cooled, permittingfuel to flow to the burners 2 and 2. The pilot light 74 burns in thechamber 3 so the burners 2 and 2 will be ignited when fuel is Isuppliedthereto. The thermo-element34 is preferably heated by the secondaryburner 2', which burner is connected in parallel with the primary burner2, which burner 2 is used for heating the incoming and the recirculatedwater.

Therefore the secondary burner 2' may be independently adjusted so as togive the correct amount of heat to the thermo-element irrespective tothe heat at which the primary burner is adjusted to operate.

As soon as the heat from the burner 2 is supplied to the bi-metallicelement 34, an expansion of this element takes place so as to moveplunger shaft 17 (Fig. 2) to the left, to close the valve 1S and openthe valve 16. In so doing, the water will then be directed from the coldwater supply pipe 58 through the valve 57 and outlet l5 to the pipe 5S,thence out of inlet pipe into the lower portion of tank 1 (Fig. l),however, the cool water which is introduced around the thermo-element73a of valve 73 will gradually become warm so as to continue to directfuel to the burners 2 and 2', after the diverter valve 1S has seated onseat 23 to divert cool water into the area immediately above theburners, thereby preventing any lag in the starting of the heating ofthe incoming water, as hot water is withdrawn.

As this operation has been taking place, the burner has been heating thewater in tank 51, and as additional cold Water is introduced through thepipe 55, heating thereof is started immediately. Thus, as fast as thewater is withdrawn through the hot water supply pipe 66 and/ or 68, morewater is supplied to the storage tank 51, with burners 2 and 2 supplyingheat to prevent a lag between the introduction of cold water and theresponse of the thermo-element.

Upon ceasing to withdraw hot water from the hot water supply pipes 66and 68, the tank 51 will have a tendency to equalize the temperature ofthe water therein. The burners 2 and 2 will continue to burn, and thewater will circulate out of the coil 63, through check valve 69 and intopipe 68 back into storage tank 51. Then the water will pass through pipe65 to complete the thermo-circulation cycle. Therefore, with thisrecirculation loop, the water in storage tank 51 is maintained at thedesired temperature.

The tank 51 is used for both heating and storage. This is particularlydesirable in a residence or wherever a small amount of hot water isrequired. The water may be maintained at a relatively low storagetemperature, as for example 80 degrees to 90 degrees F., which increasesthe useful life of the tank. The booster coil 63 has suflicient heatexchange surface to raise the water temperature from 80 or 90 degrees F.to 140 to 160 degrees F., as might be desired.

In the present system, the water is admitted through the pipe 58 intothe diverter valve 57 which may be of the same construction shown inFig. 2. This valve 57 will direct water, first through the pipe 59 andthe perforated tube 60 onto the thermostatic element 73a of the valve73, which will cool the thermostat sufficiently to open the valve 73 andpermit fuel to pass through pipe 72 to the burners 2 and 2', which willbe ignited by the pilot light 74. As soon as the burners are ignited,the bi-metallic unit 34 of the diverter valve 57 actuates the plungershaft 17 so as to shift the valve elements therein and direct the waterfrom the supply line 58 through the diverter Valve 57 and the inlet pipe5S into the lower portion of the tank 51. In so doing, the heat fromburners 2 and 2', within combustion chamber 53, will heat the lowerportion of the water tank to cause an initial heating of the cold water.

As the hot water is withdrawn from the hot water supply pipe 56, thehotter water in the upper portion of the tank 51 will be drawn throughpipe 65 into the coil 63 in the upper portion of the combustion chamber53 and Within the flue 54 where this Water is further heated. The hotWater will then pass outward from the coil 63 through the pipe 66 intothe hot water supply pipe 56. The valve 70 normally will be closed whenthe coil 63 is being utilized. After the hot Water has ceased to bewithdrawn, a circulation within the tank 51 will continue through coil63, by-pass pipe 67, check valve 69, and back through pipe 68 in the topof tank 51. This will be continued until the temperature of the waterreaches the predetermined setting of the thermostatic valve 73, whichsaid valve 73 will close and discontinue the llow of fuel through theline 72 to burners 2 and 2'. Then the bi-metallic element 34 will coolso as to move the valve members into the initial positions, as shown inFig. 2.

By having the coil 63 disposed within the combustion chamber 53,sweating or condensation of moisture on the coils is greatly reduced orcompletely eliminated, due to the fact that the water introduced intothe coil has been heated initially and it is not necessary for the coilto complete a heating operation at one step, as has been the usualpractice in coil-type heaters. By initially heating the water in thismanner, much of the lime deposit and other mineral solids are caused tosettle out in the bottom of tank 51, and may be withdrawn through drain7l, thereby freeing the Water of these mineral deposits before it entersthe coil 63. Therefore the coil 63 will be less likely to have thesedeposits accumulate therein and become clogged thereby, because much ofsuch mineral matter would be removed by the preheating. Furthermore, therange of heating of the water on the coil is not as great as if the coilhad to raise the temperature from the normal cold Water temperature, asintroduced, to the highest desired hot water temperature.

The coil 63 is removably supported within the flue 54 and the upperportion of combustion chamber 53 and it may be removed readily forcleaning and repair. This coil is provided with the customary unions ateither end thereof, and is carried by the brace 64, which supports saidcoil within flue 54. With the coil 63 thus arranged, it acts as abaiiie, whereby -a high heat recovery is possible from the spent uegases, which pass upward through the ue or vent 54 in contact with thecoil, and thus the maximum heating eiciency is obtained.

When it is desired to remove the coil 63, the pipe 65 may be capped atits lower end, and the pipe 66 from which the coil is disconnected mayalso be capped, and the valve 7) opened. Then by raising the temperaturesetting of the thermostatic valve 73, the system may be used until suchtime as the coil has been repaired and replaced. With the system thusarranged, the hot water may be then withdrawn through pipe 68, throughopen valve 70, and out through hot water supply pipe S6. The actuationof the rest of the system will not be impaired, as it will continue tooperate in the same manner, as hereinbefore described, except the waterwill low out of the tank directly through the pipe 68, instead ofpassing through the coil 63.

The pipe 66 is shown as provided with a T 75, through which water at asterilizing temperature may be withdrawn, as desired, upon the propersetting of the valve 73, and water at normal temperature may bewithdrawn through the pipes 63 and 56, upon opening the valve 70.

Due to the fact that the heater tank is operated at such lowtemperature, little or no insulation is required, las the temperaturemay be only slightly higher than the normal room temperature, asdesired.

After water has been withdrawn from the system, the burner will continueto burn and the circulation will be through check valve 69, until thewater in the tank reaches the temperature of the predetermined settingof the valve '73.

While the invention has been described in detail, in the form shown, itis to be pointed out that cold water inlet pipe 59 directs cold water toa point within the immediate region of the thermostat which controls thefuel supply to the burner or other heating element 2, so immediatelyupon turning on the burner, the cold water is directed into the heatingtank, near the bottom thereof, so the water will be in close heatexchange relation with the heat supplied by 'the burners, immediatleyupon the initial withdrawal of water.

Having thus described the invention, what is claimed is:

1. ln a water heating system for supplying liquid at two temperatures, awater tank having an inlet, a heating chamber having heating meanstherein for heating said tank, a water outlet conduit leading from theupper portion of said tank and passing through said heating chamber forsuper-heating said water, a water supply outlet connected to the upperportion of said tank for supplying water at one temperature directlytherefrom, a further water supply outlet connected to said conduitbeyond said heating chamber for supplying water at a higher temperature,a thermo-element located in the hot water zone of the water tank, meansfor directing cold water onto said thermo-element to initially cool saidthermo-element to cause an immediate supply of heating media to bedirected to the heating chamber, and means actuated by the thermoelementto redirect the cold water supply in close heat exchange relation withthe heat in said heating chamber.

2. In a water heating system for supplying heated water at twotemperatures simultaneously, a water tank having a plurality of coldwater inlets connected to a cold water supply pipe, a housing forming aheating chamber integral with said tank, heating means mounted withinsaid chamber, a pipe coil mounted within said heating chamber, a hotwater outlet pipe leading from the upper portion of said tank `andconnected with said pipe coil for passing water therethrough, a secondhot water outlet pipe connected to the upper portion of said tank forsupplying water at tank temperature directly therefrom, a conduitconnected in bridging relation between the outlet end of said pipe coiland said second hot water outlet pipe, a check valve interposed in saidconduit to permit the passage of water between said pipe in one-direction only from the pipe coil into the tank, supply conduitsconnected to the respective outlet pipes for delivering water at twotemperatures simultaneously therefrom, means for directing water fromthe cold water supply pipe to one of the inlets in the water tank, meansfor actuating the water heating means upon the direction :of cold waterto said tank inlet, and means operated in response to the actuation ofthe heating means for directing water from the cold water supply pipe tothe other tank inlet at a point in close proximity to the source ofheat.

3. 1n a water heating system for supplying heated water at twotemperatures simultaneously, a water tank having a main cold water inletand an auxiliary cold water inlet, a housing forming a heating chamberintegral with said tank, heating means mounted within said chamber, apipe coil mounted within said heating chamber, a hot water outlet pipeleading from the upper portion of said tank and connected with said pipecoil for passing water therethrough, a second hot water outlet pipeconnected to the upper portion of said tank for supplying water at tanktemperature directly therefrom, a conduit connected in bridging relationbetween the outlet end of said pipe coil and said second hot wateroutlet pipe, a check valve interposed in said conduit to permit thepassage of water from said pipe coil into said tank in one directiononly, means for diverting water from the cold water supply pipeselectively to either one of the tank inlets, a thermoelement mounted inthe tank adjacent to the auxiliary cold water inlet for controlling theheating means and the diverting means, said auxiliary cold water inletincluding means for directing cold water onto the thermo-element, andsupply conduits connected to the respective outlet pipes for deliveringhot water at two temperatures simultaneously therefrom.

4. In a water heating system for supplying water at two temperatures, atank having a ue extending upwardly therethrough, a housing at the lowerend of said tank forming a heating chamber in communication with saidl'lue, a burner in said heating chamber, a fuel supply line connected tosaid burner, a pipe coil within said heating chamber and extendingupward through said ue, a cold water inlet pipe connected in uidcommunication with said tank, a rst hot water outlet conduit connectedin uid communication with the upper portion of said tank, the lower endof said pipe coil being interconnected with said lirst hot water outletconduit of said tank to withdraw water therefrom so as to direct heatedwater into the lower end of said pipe coil, a second hot water outletconnected in liuid communication with the upper portion of said tank, aconduit interconnecting the upper end of said pipe coil and said secondhot water outlet of said tank so as to permit circulation of water fromthe upper end of said pipe coil back into said tank, a thermostat fuelcontrol Valve within said fuel supply line, the thermoelement of saidvalve extending into the hot water zone of said tank, means forinitially directing cold water around said thermo-element to initiallycool said thermo-element to cause an immediate supply of fuel to bedirected to said heating chamber to cause the simultaneous heating ofsaid water tank and said pipe coil, means for diverting the cold watersupply into close heat exchange relation with the heat in said heatingchamber after initially directing cold water around said thermo-element,and supply conduits connected to the respective outlets for deliveringwater at two temperatures simultaneously therefrom.

References Cited in the file of this patent UNITED STATES PATENTS366,074 Chase July 5, 1887 1,465,109 Boggs Aug. 14, 1923 1,724,996 DobleAug. 20, 1929 1,779,165 Hallet Oct. 21, 1930 1,894,762 Egloff Jan. 17,1933 1,972,757 Blanchard Sept. 4, 1934 2,032,447 Stack Mar. 3, 19362,290,049 Hildebrecht July 14, 1942 2,469,212 Shaw May 3, 1949 2,516,390Jensen July 25, 1950 2,540,778 Dickey Feb. 6, 1951 2,604,265 Thomas July22, 1952 2,619,944 Phillips Dec. 2, 1952

